In the book, Yarrow explains how young Internet users have grown up in a world where, for instance, instead of going to a library and rifling through card catalogs, an online search brings them directly to the information they need.

And so, she says, they expect the same thing from retail. Click a button … get it now. The phrase “I want what I want when I want it” sums up this mind-set, she says.

And because it’s all about instant, here’s a speed-read sampling of highlights from Yarrow’s most relevant sections.

Through our use of technology, we’ve become mental speed demons. Our sense of time, ability to focus, and capacity for attention have shifted gears. Because our malleable, adaptive brains respond to our experiences, the areas we use become even more efficient, faster, and more powerful, and what we don’t use becomes less effective. In other words, our brains have adapted to a new, digital world, and we’re neurologically different as a result. That digital world is a place where we scan and view rather than read, and where we’re bombarded by stimulation and constant interruptions. It is an environment that trains us to want everything faster and to crave stimulation. We’re more easily distracted, and we have less tolerance for ambiguity — and nearly everything else that requires patience.

The shift in our neurology is driven not only by the loads of information we take in but also by the often accompanying anxiety to keep track of all that information and an expectation that we be available around the clock — which requires speed and often robs us of focus.

Today’s young brains are heavily focused on scanning and processing mountains of information. Their brains are trained for speed. But it’s not only the young who are increasingly addicted to speed. Their saturation in and early use of technology makes them ultra-primed to require more stimulation and become more easily bored — but everyone’s brains are changing. We’re all less patient and less able to focus, and we all want things faster. It’s no wonder we’ve replaced the word “trend” with “trending.” We barely alight on a new idea long enough for it to be a trend; it’s just zipping by or “trending.”

When we can get what we want when we want it — be it new shoes, medical information, research for a paper, or an update on a cousin’s wedding — we come to expect immediate solutions. Impatience is the new virtue. Consumers respond to just-in-time information and ignore news before they need it. IWWIWWIWI (I want what I want when I want it) has never been more essential to satisfying the expectations of today’s consumers.

Naturally, Gen Y, who are digital natives, are the most sensitive to waiting, which is why they’re the heaviest users of same-day delivery services, despite the costs. A Shop.org survey found that this generation of shoppers was more than twice as likely as average consumers to pay for same-day delivery services.

Anticipating needs squelches impatience. Marketers can no longer wait for consumers to tell them what they need — they have to anticipate future needs. By the time someone can articulate what she wants, she’s frustrated that she doesn’t have it. Understanding your consumer’s life and figuring out what she’ll want next — whether it’s a product alteration, a faster way to check out, or more excitement — before she even knows she wants it tames impatience and creates a bond.

The self-esteem movement, political and marketing messages built on our right to happiness, and a steady stream of self-help books have all fed our current obsession with personal happiness. Along the way, we seem to have forgotten that although the pursuit of happiness is psychologically healthy, expectations of happiness and feeling entitled to happiness typically have the opposite effect.

Why? Because when we feel entitled, we’re rarely grateful. And gratitude has been positively correlated with mountains of goodies, including better sleep, stronger immune systems, higher pay, more social connections, more energy, fewer colds — and happiness. Further, those who feel entitled to happiness will be more disappointed by the actual ups and downs of life — which leads to anger and resentment.

Yale psychologist Jane Gruber attributes the negative outcomes common to self-help happiness seekers to this: “When you’re doing it with the motivation or expectation that these things ought to make you happy, that can lead to disappointment and decreased happiness.” Further, as many a great philosopher has pointed out, happiness isn’t an ending. The pleasure is in the pursuit. This runs counter to our new quick-fix mentality and the “happy life” social media comparisons mentioned in earlier chapters. We’re impatient for happiness, and our expectations are high.

Kit Yarrow is the San Francisco-based author of “Decoding the New Consumer Mind: How and Why We Shop and Buy” and “Gen BuY: How Tweens, Teens and Twenty-Somethings Are Revolutionizing Retail.” Reach her @GenBuy.